• Journal of the Korean Institute of Telematics and Electronics
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• v.21 no.2
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• pp.47-53
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• 1984

Breakdown characteristics, specifically, soft breakdown phenomena of the PN junction isolation were studied in terms of their dependence on the mask misaliglment and the amount of process-related defects. Varying the distance between the buried layer and the isolation by intentional misalignment of the isolation masts had no effects on the soft breakdown phenomena except for the change of the breakdown voltage. The soft breakdown phenomena, as characterized as a state of excessive reverse current below the breakdown voltage, were found out to result mainly from the oxidation-induced stacking faults (OSF) introduced during the fabrication process.

• Proceedings of the Korean Information Science Society Conference
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• 2007.06b
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• pp.333-338
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• 2007

시스템 가상머신 환경은 높은 하드웨어 효율성과 높은 보안을 요구하는 시스템에서 그 사용이 점차 늘어나고 있다. 최근 많이 알려진 하이퍼바이저 가상머신 시스템은 높은 아이솔레이션과 보안성을 보장하나 각 게스트 운영체제 별로 운영체제 이미지를 가지기 때문에 하드웨어 효율성이 떨어지는 반면, 컨테이너 기반 가상머신 시스템은 운영체제 이미지의 공유로 인하여 높은 자원 효율성과 확장성을 가진다. 그러나 메모리 자원의 아이솔레이션에 대하여 취약점을 갖는 문제점을 안고 있다. 본 논문에서는 컨테이너 기반 가상머신 시스템에서 동적으로 각 가상머신별로 메모리 사용량 증가에 따른 페이지 히트율-곡선(Hit-Ratio-Curve)을 측정하였다. 이 곡선을 관찰해 보면 각 가상머신의 메모리 필요량을 알 수 있으며 이를 기반으로 메모리 자원을 할당하게 될 경우 효과적으로 메모리 자원의 아이솔레이션을 제공할 수 있게 된다. 본 논문에서는 대표적인 컨테이너 기반 가상머신인 리눅스 VServer가 적용되어 있는 리눅스 2.6.17 커널에 직접 구현하였으며, Lmbench 및 리눅스 커널 컴파일 등을 통하여 오버헤드를 측정하였고 $1.6{\sim}7.2%$의 적은 오버헤드로 이를 측정할 수 있음을 확인하였다.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.48 no.2
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• pp.79-84
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• 2011

In this paper we design MIMO antenna with high isolation between antennas by using an isolation aid for WLAN. Two dual-band PIFAs which operates IEEE 802.11n are arranged symmetrically along the central axis of antenna frame and ground plane. By inserting an isolation aid between two PIFAs the isolation is improved maximum 5dB and 7dB for 2.4GHz band and 5GHz band respectively. Total efficiency is above 60%. ECC is below 0.1.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.6
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• pp.1227-1232
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• 2011

Using the notch and isolation, we investigated the insertion loss and isolation characterics of the fabricated dielectric duplexers and bandpass filters for CDMA and W-CDMA dualband. Insertion loss(Tx band) and isolation(between Tx and Rx) of duplxer were about -2.1708dB and 45dB at CDMA band, respectively. Also, in the case of W-CDMA, the insertion loss(Tx band) and isolation(between Tx and Rx) showed about -2.6946 and 100dB, respectively. Summering the aboved results, fabricated the dielectric duplexers and bandpass filters will be contributed the increase of atttenuation and the decrease of interference at CDMA and W-CDMA dualband.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.6 no.1
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• pp.28-36
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• 1995

In this paper, a design method of multiple n-way low loss power divider for x-band is propossed. To decrease loss, only two-stages of transmission lines are used with isolation resistors for match. Ex- perimental results for 3-way and 4-way power dividers have the divided power of 5.54~6.17dB and 6.76~7.37 dB, the return loss of more than 17dB and 12dB, and the isolation of more than 18dB and 10dB at center frequency, respectively, The measured results show good agreement with the theoretical analysis.

• Electronics and Telecommunications Trends
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• v.18 no.6 s.84
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• pp.41-48
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• 2003

본 논문은 아이솔레이터의 소재 파라미터에 의한 삽입손실 영향에 대하여 서술하였다. 본 논문에서는 페리자성공명반치폭($\Delta$Η), 유전손실, 자계세기 그리고 포화자화에 대한 아이솔레이터 삽입손실의 관계를 알아 보았고, 또한 공진 아래 모드를 사용한 아이솔레이터의 온도안정화 연구 및 구조설계에 대하여알아 보았다. 아이솔레이터의 온도특성은 영구자석, YIG(Yttium Iron Garnet) 페라이트 그리고 공진기로사용되는 도체 등에 의한 변화에 대하여 본 논문에서는 실험시제품을 제작하여 측정 분석하였다. 측정결과 시뮬레이션 결과와 실험시제품 측정결과가 거의 일치하는 것을 알 수 있었다. 삽입손실 0.18~0.24dB, 반사손실 27dB, 아이솔레이션 27dB 그리고 대역폭 500MHz를 얻을 수 있었다. 이때 실험에 사용한 소재 파라미터는 포화자화 550G, 유전손실, $0.0004\Delta$Η20, 유전율 14로 하였다. 또한 온도안정화실험에서는 구조를 개선하여 온도안정화를 이루었다.

• Korean Journal of Optics and Photonics
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• v.8 no.2
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• pp.142-148
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• 1997

The new type of dispersion-free optical isolator is presented and it's performance is verified by theoritical and empirical method. The dispersion-free optical isolator consists of 2 wedged birefringent materials, faraday rotator, collimating unit and focusing unit. In the test it shows that isolation is 40dB, insertion loss is 0.55dB, dispersion is 0.02ps at 1550nm

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.54 no.1
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• pp.30-34
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• 2005

This study shows the lasing characteristics of InGaAs/InGaAsP multiple-quantum-well waveguide-type depleted optical thyristor (DOT) using the vertical window. The measured switching voltage and current are 3.36 V and 10 ㎂, respectively. The lasing threshold current is 131 mA at 25 ℃. The output peak wavelength is 1570 nm at a bias current of 1.22 Ith and there is not input signal anymore in the output port. The vertical injection depleted optical thyristor - laser diode (VIDOT-LD) using the vertical-injection structure shows very good isolation between input and output signal.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.21 no.9
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• pp.850-857
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• 2011

Generally, sound-absorbing materials in vehicles are used for giving the comfort to passengers by reducing noise while driving. Materials of which targets are light weight, high performance, eco friendliness and recycling have been developed recently. In this study, sound-absorbing materials using PET(polyethylene terephthalate) hollow fibers to achieve the light weight and the high sound absorption performance are developed, and then evaluated to meet a requirement for the automotive components. The test results show that the acoustic performances of developed products having new fiber structure are better than those of the conventional product.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.9
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• pp.1727-1732
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• 2011

In order to realize a high performance(low loss, high isolation) microwave power divider/combiner, we have designed the power combiner/divider precisely in accordance with the different hight of central part. In the case of the high central part of the hight of $h_r$=10.2, a compensating part of the conical line is inserted in the conical conversion transmission line, and in the case of low central part of the hight of $h_r$=5.0, the conical conversion transmission line is remodeled into the 2-stage bend structure. In both case, the reflection characteristics are improved to 30dB over the operating frequency range of 5GHz bandwidth. A resistance is inserted between the peripheral ports so as to try to improve the isolation characteristics of the device. For the 16-divider/combiner, the isolation characteristics are improved to 10dB over the operating frequency range of 5GHz bandwidth.